public double Square()
{
double p = Perimiter() / 2;
double sideA = Point1.Distance(Point2);
double sideB = Point2.Distance(Point3);
double sideC = Point3.Distance(Point1);
return(Math.Sqrt(p * (p - sideA) * (p - sideB) * (p - sideC)));
}
public double Perimiter()
{
return(Point1.Distance(Point2) + Point2.Distance(Point3) + Point3.Distance(Point1));
}